4-Fluoroamphetamine (also known as 4-FA, 4-FMP, para-Fluoroamphetamine, PAL-303 and colloquially as Flux) is a novel synthetic substituted amphetamine compound that produces a unique progressive mixture of entactogenic and stimulant effects when administered. It is part of a series of fluorinated amphetamine analog that initially included such compounds as 2-FA, 2-FMA, and 3-FA.[1]

Anecdotal reports have described the subjective effects of 4-FA as having a moderate MDMA-likeentactogenic onset for the initial few hours of the experience that then gradually transitions into traditional amphetamine-typestimulation (for a total duration of around 6 to 8 hours) with residual effects that can last a few hours afterward.[citation needed]

4-FA is rarely found on the streets but was commonly sold as a grey area research chemical by online vendors along with related compounds such as 2-FMA and 3-FA.[2][3] Very little data exists about the pharmacological properties, metabolism, and toxicity of 4-FA, and it has only a brief history of human usage. Due to its strong psychostimulant effects, likely habit-forming properties as well as poorly understood toxicity profile, it is strongly recommended that one use proper harm reduction practices if choosing to use this substance.

Chemistry

4-Fluoroamphetamine (4-FA) is a synthetic molecule of the amphetamine family. Molecules of the amphetamine class contain a phenethylamine core featuring a phenyl ring bound to an amino (NH2) group through an ethyl chain with an additional methyl substitution at Rα. Amphetamines are alpha-methylated phenethylamines. 4-fluoroamphetamine contains a fluorine atom at R4 of its phenyl ring and is a fluorinated analogue of amphetamine.

Substitutive structure of an amphetamine molecule

Pharmacology

4-Fluoroamphetamine acts as a releasing agent and reuptake inhibitor of dopamine, serotonin, and norepinephrine producing stimulating amphetamine-like effects at lower doses and euphoric, entactogenic effects similar to MDMA at dosages above 100mg. The mechanism of action of 4-FA effectively boosts the levels of the norepinephrine, dopamine, and serotonin neurotransmitters in higher doses in the brain by binding to and partially blocking the transporter proteins that normally remove those monoamines from the synaptic cleft. This allows dopamine, norepinephrine, and serotonin to accumulate within the brain, resulting in stimulating, euphoric and entactogenic effects.[4][5][6]

Subjective effects

It is commonly reported that the first three to four hours of 4-FA present distinct entactogenic effects that have been reported as feeling somewhat similar to MDMA although not quite as powerful. This is thought to correlate with the duration in which it is promoting the release of serotonin (in addition to dopamine and norepinephrine). After this first phase of the experience, the effect then shifts towards something which feels like classic amphetamine stimulation which can persist for an extended period.[citation needed]

Do not use 4-FA if you have a history of heart-related issues or experience a severe headache after its use. We have been made aware of a report released by Trimbos-instituut[7] and Nationaal Vergiftigingen Informatie Centrum[8] (NVIC), describing incidents of strokes after an increased use of 4-FA. In addition to the common amphetamine-like effects (agitation, anxiety, tachycardia, hypertension, chest pain et al.), serious cardio- and cerebrovascular complications have been reported, including rhythm (sinus arrhythmia, ventricular extrasystoles (bigeminy), conduction disturbances) and acute cardiac failure. Although a causal relationship has not been confirmed, when presented with a severe headache and lateralization after 4-FA usage, a medical evaluation at an emergency department should be conducted immediately. [9]

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWikicontributors. These effects should be taken with a grain of salt and will rarely (if ever) occur all at once, but heavier doses will increase the chances of inducing a full range of effects. Likewise, adverse effects become much more likely on higher doses and may include serious injury or death.

Physical effects

Stimulation - The first few hours of the 4-FA experience are commonly reported to have overtones of the type of sedation that is associated with the serotonin-releasing properties of entactogens like MDMA. After these entactogenic effects fade and the stimulating effects become predominant. The stimulation which 4-FA produces throughout the entirety of the experience be described as being slightly weaker in intensity to amphetamine and less forceful than traditional dopaminergic stimulants such as cocaine.

Spontaneous bodily sensations - The "body high" of 4-FA can be characterized as a moderate to extreme euphoric tingling sensation that encompasses the entire body. It is capable of becoming overwhelmingly pleasurable at higher doses. This sensation maintains a consistent presence that steadily rises with the onset and hits its limit once the peak has been reached.

Physical euphoria - This effect is extremely intense when compared to its physical stimulation.

Vibrating vision - At high doses, a person's eyeballs may begin to spontaneously wiggle back and forth in a rapid motion, causing the vision to become blurry and temporarily out of focus. This is a condition known as nystagmus and is considered to be harmless in most cases.

Seizure - This is a rare effect but is thought to be able to occur in those predisposed to them, especially when taking heavier-than-recommended doses or redosing while in physically taxing conditions such as being dehydrated, fatigued, undernourished, or overheated.[citation needed]

Cognitive euphoria - This effect can be described in its manifestation as a series of euphoric waves that recede and reappear randomly throughout the experience. It is most present at dosages above 100mg.

Delirium & Confusion - This effect typically only occurs with overly high doses, and is associated with temperature dysregulation and overheating, particularly when 4-FA is taken in crowded, physically strenuous environments that leaves the user unable to cool off, rest, or rehydrate adequately.

Unity and interconnectedness - Experiences of unity, oneness, and interconnectedness are sometimes reported with 4-FA. This component most consistently manifests itself at higher doses during the empathogenic phase, within large crowds at raves and musical events in the form of "becoming one with the crowd." Music is said to intensify this effect as well consistently.

After effects

The effects which occur during the offset of a stimulant experience generally feel negative and uncomfortable in comparison to the effects which occurred during its peak. This is often referred to as a "comedown" and occurs because of neurotransmitter depletion. Its effects commonly include:

Toxicity and harm potential

The toxicity and long-term effects of recreational 4-FA use have only scarcely been studied because 4-FA has very little history of human usage. Anecdotal evidence, as well as several case reports, suggest there is a small to moderate individual health risk associated with the use of 4-FA. Among these, it appears there is an especially a high risk for acute cardiovascular toxicity. Some people in the Netherlands, only using a moderate dose, have died due to cardiac arrest or suffered severe brain damage due to a stroke. The mechanism of this acute toxicity is not yet known, but it seems as though the stroke starts off as an intense headache or even a migraine attack, that slowly worsens.[10]

It is also worth noting that 4-FA is particularly caustic in comparison to other compounds and can, therefore, cause chemical burns within the nasal passage and throat if it is insufflated. This method of administration is discouraged.

Tolerance and addiction potential

As with other stimulants, the chronic use of 4-FA can be considered moderately addictive with a high potential for abuse and is capable of causing psychological dependence among certain users. When addiction has developed, cravings and withdrawal effects may occur if a person suddenly stops their usage.

Tolerance to many of the effects of 4-FA develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). This is how long it takes to reduce the tolerance for the stimulating effects. Tolerance for the entactogenic effects may take a longer period to reduce. 4-FA presents cross-tolerance with all dopaminergicstimulants, meaning that after the consumption of 4-FA all stimulants will have a reduced effect.

Psychosis

4-FA, like other stimulants, can result in a stimulant psychosis that may present with a variety of symptoms (e.g., paranoia, hallucinations, or delusions).[12][13] A review on treatment for amphetamine, dextroamphetamine, and methamphetamine abuse-induced psychosis states that about 5–15% of users fail to recover completely.[13][14] The same review asserts that, based upon at least one trial, antipsychotic medications effectively resolve the symptoms of acute amphetamine psychosis.[13]

Dangerous interactions

Although many psychoactive substances are safe to use on their own, they can quickly become dangerous or even life-threatening when combined with other substances. The following lists some known dangerous combinations, but may not include all of them. A combination that appears to be safe in low doses can still increase the risk of injury or death. Independent research should always be conducted to ensure that a combination of two or more substances is safe to consume. Some interactions listed have been sourced from Tripsit.

PCP - This combination can easily lead to hypermanic states.

Opioids - Stimulants increase respiration rate allowing a higher dose of opiates. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.

MXE - Risk of tachycardia, hypertension, and manic states.

Mushrooms - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.

Mescaline - The focus and anxiety caused by stimulants is magnified by psychedelics and results in an increased risk of thought loops.

LSD - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.

Ketamine - No unexpected interactions, though likely to increase blood pressure but not an issue with sensible doses. Moving around on high doses of this combination may be ill advised due to risk of physical injury.

GHB - Stimulants increase respiration rate allowing a higher dose of sedatives. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.

GBL - Stimulants increase respiration rate allowing a higher dose of sedatives. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.

DMT - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.

Cocaine - This combination of stimulants will increase strain on the heart. It is not generally worth it as Cocaine has a mild blocking effect on dopamine releasers like amphetamine.

Cannabis - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.

Caffeine - This combination of stimulants is not generally necessary and may increase strain on the heart, as well as potentially causing anxiety and greater physical discomfort.

Alcohol - Drinking on stimulants is risky because the sedative effects of the Alcohol are reduced, and these are what the body uses to gauge drunkenness. This typically leads to excessive drinking with greatly reduced inhibitions, high risk of liver damage and increased dehydration. They will also allow you to drink past a point where you might normally pass out, increasing the risk. If you do decide to do this then you should set a limit of how much you will drink each hour and stick to it, bearing in mind that you will feel the Alcohol and the stimulant less. Extended release formulations may severely impede sleep, further worsening the hangover.

2C-x - The anxiogenic and focusing effects of stimulants increase the chance of unpleasant thought loops. The combination is generally uneccessary because of the stimulating effects of psychedelics. Combination of the stimulating effects may be uncomfortable.

DXM - Both substances raise heart rate, in extreme cases, panic attacks caused by these drugs have led to more serious heart issues.

DOx - The combined stimulating effects of the two can lead to an uncomfortable body-load, while the focusing effects of amphetamine can easily lead to thought loops. Coming down from Amphetamines while the DOx is still active can be quite anxiogenic.

5-MeO-xxT - The anxiogenic and focusing effects of stimulants increase the chance of unpleasant thought loops. The combination is generally unnecessary because of the stimulating effects of psychedelics.

2C-T-x - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences. In extreme cases, they can result in severe vasoconstriction, tachycardia, hypertension, and in extreme cases heart failure.

25x-NBOMe - Amphetamines and NBOMes both provide considerable stimulation. When combined they can result in tachycardia, hypertension, vasoconstriction and in extreme cases heart failure. The anxiogenic and focusing effects of stimulants are also not good in combination with psychedelics as they can lead to unpleasant thought loops. NBOMes are known to cause seizures and stimulants can increase this risk.

ΑMT

Tramadol - Tramadol and stimulants both increase the risk of seizures.

MAOIs - MAO-B inhibitors can increase the potency and duration of phenethylamines unpredictably. MAO-A inhibitors with amphetamine can lead to hypertensive crises.

Legal status

Austria: 4-FA is illegal to possess, produce and sell under the NPSG (Neue-Psychoaktive-Substanzen-Gesetz Österreich).[citation needed]

Brazil: 4-FA is illegal to possess, produce and sell as it is listed on Portaria SVS/MS nº 344.[15]

Canada: 4-FA would fall under Schedule I as it is considered an analog of amphetamine.[16]

France: 4-FA was added to the list of illicit substances in March 2011.[citation needed]